latex公式后加编号

\tag{1.2}

\[\begin{equation*} \tag{1.2} \begin{aligned} & \mathop{\min}\limits_{\phi \in \Phi,f_0\in F, w \in \Delta^{T-1}} \hat{L}_0(\phi,f_0) \\[2ex] &subjet \ \ to\ \ \phi\in \mathop{\arg\min}\limits_{\varphi\in \Phi} \ \mathop{\min}\limits_{\{ f_t \}\subset F} w_t \hat{L_t}(\varphi,f_t) \end{aligned} \end{equation*} \]

\begin{equation*} \tag{1.2}
	\begin{aligned} 
		& \mathop{\min}\limits_{\phi \in \Phi,f_0\in F, w \in \Delta^{T-1}} \hat{L}_0(\phi,f_0)
        \\[2ex]
		&subjet \ \ to\ \ \phi\in \mathop{\arg\min}\limits_{\varphi\in \Phi} \ \mathop{\min}\limits_{\{ f_t \}\subset F} w_t  \hat{L_t}(\varphi,f_t)
	\end{aligned}
\end{equation*}